کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6410030 | 1629916 | 2016 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Changes in monthly flows in the Yangtze River, China - With special reference to the Three Gorges Dam Changes in monthly flows in the Yangtze River, China - With special reference to the Three Gorges Dam](/preview/png/6410030.png)
- Temperature generally trends upward 1955-2014; no evidence this affects discharge.
- There has been little detectable trend in precipitation.
- Discharge in upper catchment decreased in Oct after TGD finished 2003.
- Discharge in upper catchment increased Jan, Feb, Mar after TGD finished 2003.
- Lower basin flow increases in Dec to Mar occurred gradually over period of record.
- All changes explained by the operation of hydroelectric and flood control dams.
- Observed changes are not detrimental to the normal functioning of the Yangtze.
SummaryMuch has been written on the hydrology of the Yangtze River in China, especially since the construction of the Three Gorges Dam. Given the range of views in the literature on the impacts of dams and other natural and anthropogenic activities in the catchment on monthly flows, we here set out to analyse the behavior of monthly flows over the period of record 1955-2014. In the literature, the Three Gorges dam has been singled out for particular comment, mostly adverse. In this paper we analyse trend in temperature, precipitation and discharge of the Yangtze River at the monthly time scale over a period that includes the 11Â years since the Three Gorges Dam came into operation. The results show that for the upper basin, there has been a marked increase in discharge in the low flow months of January to March that began abruptly in 2003 and an abrupt decrease in flow in October at the same time. Similar changes are found for discharge from the lower basin but in that case the changes have occurred gradually over the period of record. These changes are the outcome of the operation of hydroelectric and flood control dams that have been built continuously in the lower basin since 1955 while in the upper basin the building of the Three Gorges Dam began a phase of rapid dam building not seen in the lower basin. The decreased flows in the late summer and autumn are not of sufficient magnitude to cause any problems for navigation or water supply. The enhanced flows in the winter low flow period are beneficial in that they reduce the likelihood of salt water intrusions in the estuary adversely affecting the supply of freshwater to Shanghai.
Journal: Journal of Hydrology - Volume 536, May 2016, Pages 293-301